1. Field of the Invention
The present invention is directed towards a grooved aspiration pump roller-head assembly. More particularly, the present invention is directed towards a self-engaging peristaltic pump head having a thread for pulling a loop of tubing onto the roller-head assembly.
2. Description of Related Art
It is well known for a peristaltic pump to use a pump cartridge having a loop of tubing which is placed over a roller-head assembly. The tubing is then either stretched, such that the tubing is pinched off between the rollers of the roller-head assembly or is pressed between the rollers and a backing plate. When the roller-head assembly is rotated, fluid is persitaltically pumped through the loop of tubing from a surgical site.
To ensure proper operation of the peristaltic pump, it is necessary that the loop of tubing is properly mounted on the roller-head assembly. There have been many known schemes to ensure the tubing is properly loaded onto the roller-head assembly. These include U.S. Pat. No. 4,861,242 to Finsterwald and U.S. Pat. No. 5,588,815 to Zaleski, II. These two patents both teach the use of a notch which extends beyond a forward face of a roller-head assembly and acts to engage or grab the loop of tubing, and as the roller-head assembly is rotated, the notch pulls the loop of tubing onto the rollers of the roller-head assembly. There have been other structures, such as tapering the roller-heads in order to encourage the loop of tubing to be drawn onto the rollers. While these prior art schemes may be effective in their own way, it would be desirable to have a easily manufactured roller-head assembly that would reliably work with loops of tubing that may be severely misaligned with the roller-head assembly and still be drawn onto the rollers of the roller-head assembly and properly mounted for operation of the peristaltic pump.